A pressure sensor assembly may be in multi-part form. In order to produce the pressure sensor assembly, the sensor housing element together with the pressure sensor and the base housing element are produced. Both the sensor housing element and the base housing element have a recess. It may be provided, in this context, that the recess of the sensor housing element is a blind recess, that is, it does not fully reach through the sensor housing element. By contrast, it is usually provided that the recess of the base housing element does fully reach through it. Thereafter, the sensor housing element and the base housing element are positioned so that the recess of the base housing element is flush with the recess of the sensor housing element, so that a continuous recess is formed. The pressure sensor is provided in the recess of the sensor housing element, in this instance. An operative pressure connection of the environment to the pressure sensor is produced by the continuous recess. After the alignment of the sensor housing element and the base housing element in such a way that the continuous recess created, the sensor housing element and the base housing element are welded together. This may be done, for example, using laser welding, resistance welding or electron beam welding.
In this context, in a connecting area of the base housing element or of the sensor housing element, in which the welding seam will subsequently be present, a weld pool backing is usually provided, in order to prevent material from getting into the recess during the welding. The weld pool backing is formed, in this context, by a tapering in the recess of the base housing element and the sensor housing element. In addition, a notch is created on the welding seam or on the weld root, because of the welding. The effect of the notch that is thus present reduces the stability of the welding connection, and thereby of the entire pressure sensor assembly. In addition to the effect of the notch, there is the circumstance that, because of the weld pool backing, a discontinuity in the rigidity between the sensor housing element and the base housing element superimposes additional shear stresses on the welding seam, or rather, the welding connection. The welding connection is additionally weakened by fusion occurring during the welding process, especially when highly tempered steels are used for the sensor housing element and/or the base housing element.
Consequently, conventional methods for producing the pressure sensor assembly are suitable only for producing pressure sensors for a certain pressure range. Conventionally, for instance, when using pressure sensor assemblies produced in this way, nominal pressures of up to 2400 bar are able to be measured. If the geometry of the sensor housing element or of the base housing element is to be optimized with respect to a higher resistance to compression of the pressure sensor assembly, this always has the effect that the welding becomes more difficult to carry out. In sensor housing elements and base housing elements which are designed only for high resistance to compression, the welding is frequently not possible at all. The geometry of the sensor housing element and the base housing element can therefore always be only a compromise between producibility and resistance to compression. European Patent No. EP 1 518 099 E1, for example, describes a device for measuring pressure, in which a pressure measuring cell made of high-grade steel is welded together with a connection piece.